The veracity of a lesson I sometimes forget: “Never prejudge a show you are about to see” has been emphatically reinforced by the Flagler Playhouse production of “Annie Jr.” — completing a two-weekend run.

Cheers to Jamie Irvine, a young woman with a rich theatrical background focused around Pittsburgh, making her directorial, choreographic, and set design debut here. Jamie obviously knows her stagecraft. Everything about this production — the multiple sets, props, pre-recorded accompaniment of its memorable musical score, costuming, acting and dancing — all are neat, compact, understated , genuinely enthusiastic where appropriate ... just right. (Of course, credit must be shared with her competent staff.)

The show’s heroine, plucky Annie, is played with amazing grace and effectiveness by Cassidy Van Brink, in a tightly-curled, bright-red wig. She’s great in the role, her singing strong, her emotional responses just right. The audience pulls for her all the way. Huggable dog Sandy is played by Abigail Mantell on all fours, with drooping paste-on ears.

The cast is surprisingly large (about 30 in all), making its first full appearance, blanketing the balconies on either side and the stage, with its winning rendition of “N.Y.C.,” and again at the finale with a reprise of “Tomorrow.”

The eight “orphan” girls captured my heart, particularly the littlest one among them, Emma Burke — who looks to be no more than six or eight. (The others: Gianna Lazzano; Molly Maresca; Emily Callahan; Savannah Dacosta; Amy Raleigh; Kristina Mercado and Savanna Peterson)

They’re all wonderful, but that little darling throws herself into every song, every dance with such vigor and expression, you melt.